Predictive Compensation Control for Current Phase Delay of Hybrid Active Power Filter

According to the phase delay of hybrid active power filter output current, the causes are analyzed in this paper, including passive filters, coupling transformer and output filter. The phase delay mentioned above is named generalized delay, which is variable with different frequency. In order to eliminate the effects of generalized delay, a novel pi -aimed Smith predictor is established based on the fact that there is a 180 degree delay between output current and load harmonic current, which are negative in polarity. Applying generalized integrators with excellent performances of frequency division, a generalized integral control and its discrete iterative algorithm based on predictive compensation at different frequency for generalized delay is proposed. The feasibility and effectiveness of this control method is verified by PSIM simulation and experimental results.